kmscube corrupted/flickering when texturing enabled

[anszom]

kmscube -M rgba shows corrupted image, some of the faces flicker (background shows through). Also, the animation isn't as smooth, there is some back-and-forth frame stutter.

kmscube -M smooth works fine

platform: raspberry pi 4 with fkms

[anszom]

Here's how it looks: https://youtu.be/UX82__c_GPs

[anszom]

I've re-checked with mesa built from git master, and the results are the same